Innovative semiconductor architecture opens a new era in nanoelectronics
As transistors are the key parts of integrated circuitry, they play an important role in the proper operation of the complete micro-electronic device. One of the most commonly used types of transistors is the Metal Oxide Semiconductor Field Effect Transistors (MOSFETs). Moving to the nanometre regime, the components of the MOSFETs have been extensively analysed and optimised for the reliable operation of the device. One of the primary focuses of source/drain engineering is the Schottky barrier height of silicide contact for good current drivability. In the case of Schottky source/drain MOSFETs the normally implanted/diffused highly doped regions for the source/drain are replaced with silicide regions that behave as metals do. Moreover, a p-type silicided source/drain with a low Schottky barrier height also displays a high thermal stability. The SODAMOS project designed, optimised and fabricated a set of accumulated low Schottky barrier MOSFETs on Silicon On Insulator (SOI) to solve the critical problems associated to the source/drain architecture. Compared to conventional architectures this technology showed a better performance in terms of immunity to short channel effects, suppressed sensitivity to dopant fluctuation and reduced source/drain specific contact resistance. Moreover, the Schottky source/drain contacts were found capable to inhibit problems related to the tight control of source/drain doping. At the material engineering level, the development of Pt elementary blocks was found to be compatible with current CMOS already running on process line. This shows a high potential of this laboratory concept to become an industrially attractive solution. Furthermore, this innovation meets the requirements of the International Technology Roadmap for Semiconductors (ITRS) moving towards the 35nm and ultimately 22nm technology node.
